Light Emitting Apparatus

ABSTRACT

A fluorescent lamp type light emitting apparatus is provided. The light emitting apparatus comprises a cover, a light emitting module, radiation pads, and cap parts. The cover comprises a first cover and a transmissive second cover coupled to the first cover. The light emitting module comprises a plurality of light emitting diodes in the cover. The radiation pads are disposed on the light emitting module. The cap parts comprise electrode terminals at both ends of the cover.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit under 35 U.S.C. §119 of KoreanPatent Application No. 10-2008-0095451, filed Sep. 29, 2008, which ishereby incorporated by reference in its entirety.

BACKGROUND

The present disclosure relates to a fluorescent lamp type light emittingapparatus.

Research and development on illuminators has been carried out to improveenergy efficiency and satisfy requirements of users. Illuminators, suchas incandescent lamps, fluorescent lamps and three-wavelength lamps areconvenient to manufacture and use, and are thus very popular, but theyare uneconomical due to their short service life and low energyefficiency. To address this limitation, light emitting diode (LED)illuminators, which have improved service life and energy efficiency,have been developed and sold.

Such LED illuminators have 25 W or lower power consumption, and mayreduce electricity fees by about 30% or more. In addition, since LEDilluminators are semi-permanent, their applications are diverse.

BRIEF SUMMARY

Embodiments provide a fluorescent lamp type light emitting apparatuscomprising light emitting diodes.

Embodiments provide a fluorescent lamp type light emitting apparatusthat can effectively release heat generated from light emitting diodesto a first cover, and diffuse light through a diffusion second cover.

Embodiments provide a fluorescent lamp type light emitting apparatusthat can release heat through a silicon radiation pad of a lightemitting module and a first cover.

Embodiments provide a fluorescent lamp type light emitting apparatusthat can vary brightness and/or color of a light emitting diode.

Embodiments provide a fluorescent lamp type light emitting apparatusthat can control dimming of an LED according to a signal sensed by anoptical sensor.

An embodiment provides a light emitting apparatus comprising: a covercomprising a first cover and a second cover coupled to the first cover,wherein the cover is formed in tube shape and at least one of the firstcover and second cover is transmissive; a light emitting modulecomprising a plurality of light emitting diodes in the cover; aplurality of radiation pads on the light emitting module; and cap partscomprising electrode terminals coupled at both ends of the cover.

An embodiment provides a light emitting apparatus comprising: a lightemitting module comprising a circuit board and a light emitting diodearray under the circuit board; a first cover on the light emittingmodule; a transmissive cover coupled to the first cover; a diffusionmember at the transmissive cover; a plurality of radiation pads on thecircuit board of the light emitting module; and a plurality of cap partsat both ends of the first cover and the transmissive cover.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features will be apparent fromthe description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view illustrating a fluorescent lamptype light emitting apparatus according to an embodiment.

FIG. 2 is a perspective view illustrating the fluorescent lamp typelight emitting apparatus of FIG. 1.

FIG. 3 is a cross-sectional view illustrating the fluorescent lamp typelight emitting apparatus of FIG. 2.

FIG. 4 is cross-sectional view illustrating a diffusion sheet providedto the fluorescent lamp type light emitting apparatus of FIG. 3,according to an embodiment.

FIG. 5 is a schematic view illustrating a structure for rotating a firstcover and a second cover according to an embodiment.

FIG. 6 is a circuit diagram of light emitting diode arrays according toan embodiment.

FIG. 7 is a circuit diagram of light emitting diode arrays according toanother embodiment.

FIG. 8 is a block diagram of a light emitting apparatus according to anembodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments of the presentdisclosure, examples of which are illustrated in the accompanyingdrawings.

FIG. 1 is an exploded perspective view illustrating a fluorescent lamptype light emitting apparatus 100 according to an embodiment, FIG. 2 isa perspective view illustrating the fluorescent lamp type light emittingapparatus 100 of FIG. 1, and FIG. 3 is a cross-sectional viewillustrating the fluorescent lamp type light emitting apparatus 100 ofFIG. 2.

Referring to FIG. 1, the light emitting apparatus 100 comprises a firstcover 110, a second cover 120, a light emitting module 130, and capparts 150.

The light emitting apparatus 100 may be defined as a straight pipe typecylindrical lamp, a straight pipe type rod lamp, a straight pipe typetube lamp, or a tube type lamp. Hereinafter, the light emittingapparatus 100 will be described as a straight pipe type cylindrical lampfor convenience in description.

The first cover 110 may have a hemispheric shape or a half-cylindricalshape. The first cover 110 may have a length corresponding to apredetermined length of a straight pipe type fluorescent lamp. The firstcover 110 is formed as a heat sink cover. The first cover 110 may beformed of metal, e.g., aluminum. A plurality of heat sink pins 111 and112 protrude from an inner circumference and/or an outer circumferenceof the first cover 110, and may have the same shape or different shapesfrom each other, but the shape is not limited thereto.

The heat sink pins 111 and 112 may be disposed in the longitudinaldirection of the first cover 110 and/or in the circumferential directionof the first cover 110, but embodiments are not limited thereto.

The first cover 110 can effectively release heat generated from thelight emitting module 130 in the full range of the first cover 110.

The second cover 120 is formed as a transmissive front cover. The secondcover 120 may have a hemispheric shape or a half-cylindrical shape. Thesecond cover 120 may be formed of light transmissive plastic (e.g.polycarbonate (PC)). An inner circumference 121 of the second cover 120may be provided with a diffusion member 129 as illustrated in FIG. 3.The diffusion member 129 diffuses light emitted from the light emittingmodule 130 to inhibit glare caused by light transmitted by the secondcover 120. The diffusion member 129 may be a diffusion sheet or beformed by application of a diffusion material, but is not limitedthereto.

Coupling protrusions 115 are disposed at both edges of the first cover110. Coupling grooves 125, which catch the coupling protrusions 115, aredisposed at both edges of the second cover 120. The coupling protrusions115 and the coupling grooves 125 may be coupled in a hook arrangementand be replaced with each other, but are not limited thereto.

Supports 114 protrude inward along lateral edges of the first cover 110,and are parallel to each other.

The light emitting module 130 may be fixed to the bottom surface of thesupports 114.

A pad contact 113 is disposed at the center of the inner circumferenceof the first cover 110. The pad contact 113 is provided with a planarsurface that is disposed in the longitudinal direction of the firstcover 110 and has a width corresponding to the widths of radiation pads137.

The light emitting module 130 comprises a circuit board 132 and lightemitting diodes 133. The circuit board 132 may comprise one or moremetal core printed circuit boards (PCBs) that have a high heat releaserate. The circuit board 132 may have a length and a width such that thecircuit board 132 can be disposed in the light emitting apparatus 100,but is not limited thereto.

A control module 160 is disposed on the circuit board 132, and comprisesa driving circuit and a control circuit, and controls on/off, dimmingand color temperature of the light emitting diodes 133. The controlmodule 160 receives DC power through a plurality of power lines that areprovided to the circuit board 132.

The bottom of the circuit board 132 is provided with an interconnectionpattern, and the light emitting diodes 133 are arrayed on the bottom ofthe circuit board 132.

The light emitting diodes 133 may be arrayed in at least one line, andbe connected to each other in parallel or in series. The number of theconnected light emitting diodes 133 may be varied according to a socketfor a straight pipe type fluorescent lamp, the luminous intensity of thelight emitting apparatus 100, or input power, but is not limitedthereto. The circuit board 132 may be provided with a zener diode (notshown) for protecting the light emitting diodes 133.

The light emitting diodes 133 may emit a target light, e.g. while light,or lights emitted from two kinds of light emitting diodes may be mixedto obtain a target light. A target light or light color of the lightemitting diodes 133 may be varied, and thus, is not limited. Variouspackages comprising a dome-type package with a wafer level package (WLP)may be used for the light emitting diodes 133.

The radiation pads 137 may be disposed on the circuit board 132. Theradiation pads 137, which are heat conductive pads formed of silicon,may stand vertically on the circuit board 132.

Since the radiation pads 137 are in close contact with the top of thecircuit board 132, the radiation pads 137 release heat generated fromthe circuit board 132, and may release the heat through the first cover110.

The radiation pads 137 have a width that is less than that of thecircuit board 132, and are spaced a predetermined distance from eachother. The radiation pads 137 may be arrayed in the first cover 110 at aregion except for a region 135A for the control module 160.

The radiation pads 137 conduct heat generated from the circuit board 132to the first cover 110. The radiation pads 137 may be coupled to thecircuit board 132 through a conductive tape, a screw member, or a heatconductive resin.

The radiation pads 137 and the first cover 110 effectively release heatgenerated from the circuit board 132 to inhibit efficiency deteriorationof the light emitting diodes 133 and heat distortion of the second cover120.

The first cover 110 is coupled to the second cover 120 to form a cover,which protects the light emitting module 130 therein.

The cap parts 150 may be coupled to both ends of the cover having thefirst cover 110 and the second cover 120, and can be formed of plasticthat is electrically insulated and resistant against high temperature. Aplurality of electrode terminals 153 protrude outward from each of thecap parts 150, and are electrically connected to the circuit board 132of the light emitting module 130. The electrode terminals 153 of the capparts 150 may be connected to the circuit board 132 of the lightemitting module 130 through a wire member or connector member, or theelectrode terminal 153 may be directly connected to the circuit board132, but the connection thereof is not limited thereto.

Cover guides 155 are provided to outer circumferences of the cap parts150, and protrude in ring shape to be in close contact with the outercircumferences of the first cover 110 and the second cover 120. Thecover guides 155 may be fitted around both sides of the first cover 110and the second cover 120.

As described above, the light emitting diodes 133 are provided to thebottom of the circuit board 132 of the light emitting module 130, andthe radiation pads 137 and the control module 160 comprising a driverare disposed on the top of the circuit board 132.

The radiation pads 137 may be fixed to the circuit board 132 through aconductive tape, a screw member, or heat conductive resin, and have apredetermined shape and a predetermined area, and are spaced apredetermined distance from each other.

The circuit board 132 of the light emitting module 130 may be fixed tothe supports 114 in the first cover 110 through a coupling member suchas adhesive or a screw. The radiation pads 137 of the light emittingmodule 130 may be close to or be in contact with the inner circumferenceof the first cover 110.

After the light emitting module 130 is coupled to the supports 114 inthe first cover 110, the first cover 110 and the second cover 120 arecoupled to each other in the straight pipe type in the state where thefirst cover 110 and the second cover 120 face each other.

The coupling protrusions 115 provided to both edges of the first cover110 are coupled to the coupling grooves 125 provided to both edges ofthe second cover 120. The coupling protrusions 115 are disposed in thelongitudinal direction of the first cover 110, and the coupling grooves125 have shapes corresponding to the coupling protrusions 115, in thelongitudinal direction of the second cover 120. The coupling protrusions115 are coupled to the coupling grooves 125 in hook arrangement toconstitute the cover fowled of the first cover 110 and the second cover120.

Referring to FIG. 3, a receiving portion 126 is disposed in each of thecoupling grooves 125 of the second cover 120 in the longitudinaldirection of the second cover 120, and elastic bands 127 are disposed inthe receiving portions 126. The elastic band 127 may be provided inplurality in each of the receiving portions 126. When the couplingprotrusions 115 of the first cover 110 are inserted into the receivingportions 126, the elastic bands 127 are compressed to transmit theirelastic force upward to the coupling protrusions 115, so that thecoupling protrusions 115 are caught and coupled to the coupling grooves125. Since the elastic bands 127 push the coupling protrusions 115 ofthe first cover 110 to the coupling grooves 125, the first cover 110 isinhibited from being removed from the second cover 120.

Since the coupling protrusions 115 and the coupling grooves 125 arecoupled in first cover 110 and the second cover 120, the couplingprotrusions 115 and the coupling grooves 125 do not protrude from theouter surface of the cover.

The light emitting apparatus 100 is embodied by coupling the cap parts150 to both the ends of the first and second cover 110 and 120. The capparts 150 cover both ends of the light emitting apparatus 100 and allowsthe electrode terminals 153 to protrude outward.

As described above, the electrode terminals 153 of the cap parts 150 maybe connected to the circuit board 132 of the light emitting module 130through a wire member or connector member, or the electrode terminals153 may be directly connected to the circuit board 132.

The electrode terminals 153 provided to the cap parts 150 are connectedto a socket (not shown) for a fluorescent lamp to supply power to thelight emitting apparatus 100.

When power is supplied to the electrode terminals 153 of the lightemitting apparatus 100, the light emitting diodes 133 of the lightemitting module 130 emit light.

The second cover 120 diffuses light emitted from the light emittingdiodes 133 and transmits the light to the outside. Light emitted fromthe light emitting diodes 133 is diffused uniformly to the whole of anilluminated region by the diffusion member 129 provided to the innercircumference 121 of the second cover 120.

The radiation pads 137 and the first cover 110 having a concave-convexstructure release heat emitted from the light emitting diodes 133.

FIG. 4 is a cross-sectional view illustrating a diffusion sheet 129Aprovided to the second cover 120 of FIG. 3, according to anotherembodiment.

Referring to FIG. 4, a insertion hole 121A, having a hemispheric shapeor a half-cylindrical shape, is disposed in the second cover 120 in thelongitudinal direction of the second cover 120, and the diffusion sheet129A is inserted into the insertion hole 121A. Since the diffusion sheet129A is disposed in the second cover 120, an additional coupling processfor the diffusion sheet 129A is not required.

FIG. 5 is a schematic view illustrating a structure for rotating thefirst cover 110 and the second cover 120 according to an embodiment.

Referring to FIG. 5, rotation guide protrusions 117 are provided at bothends of the first cover 110 on the outer circumference of the firstcover 110, and rotation guide holes 157 are provided at the cover guides155 of the cap parts 150.

When the cap parts 150 are coupled to both the ends of the first cover110 and the second cover 120, the rotation guide protrusions 117 of thefirst cover 110 are fitted into the rotation guide holes 157 of the capparts 150.

The rotation guide protrusions 117 may be provided to the second cover120, and the rotation guide holes 157 may be further provided to thelower side of the cap parts 150. The cover formed of the first cover 110and the second cover 120 rotates along the cap parts 150.

The electrode terminals 153 of the cap parts 150 may be coupled to thesocket for a fluorescent lamp. In this case, the cap parts 150 arefixed, and the first cover 110 and the second cover 120 may be rotatablerelative to the fixed cap parts 150 within a predetermined angle (e.g.0<rotation angle<+90° or −90°) through the rotation guide protrusions117 and the rotation guide holes 157. Accordingly, the direction oflight emitted from the light emitting apparatus 100 may be adjustedwithin about +90° or −90°.

Although a lock structure of the rotation guide protrusions 117 and therotation guide holes 157 is used to rotate the light emitting apparatus100, a thread member, or a bearing member may be used to rotate thelight emitting apparatus 100.

FIG. 6 is a circuit diagram of first and second light emitting diodearrays 133A and 133B according to an embodiment.

Referring to FIG. 6, a light emitting module comprises the first andsecond light emitting diode arrays 133A and 133B.

The first and second light emitting diode arrays 133A and 133Bcomprising the light emitting diodes 133 are connected to each other inparallel in a forward direction with respect to power terminals P1 andP2. The number of the light emitting diodes 133 connected to the lightfirst and second emitting diode arrays 133A and 133B may be adjustedaccording to socket size, luminous intensity, or input power.

The light emitting diode arrays 133A and 133B may emit lights havingdifferent color temperatures from each other. For example, the firstlight emitting diode array 133A emits white light having a colortemperature ranging from about 5000 to 8000K, and the second lightemitting diode array 133B emits white light having a color temperatureranging from about 2000 to 3000K.

The first and second light emitting diode arrays 133A and 133B havedifferent correlated color temperatures (CCTs) from each other to vary amixed color thereof. In this case, a color temperature is varied betweenabout 2000 and 8000K by mixing correlated color temperatures of thefirst and second light emitting diode arrays 133A and 133B and bycontrolling optical output of the light emitting diodes 133.

FIG. 7 is a circuit diagram of first and second light emitting diodearrays 133C and 133D according to another embodiment.

Referring to FIG. 7, the first and second light emitting diode arrays133C and 133D may be connected in parallel in a reverse direction withrespect to power terminals P3 and P4. The first and second lightemitting diode arrays 133C and 133D in parallel in the reverse directionare sequentially driven by AC power. The number of light emitting diodesconnected to the first and second light emitting diode arrays 133C and133D may be adjusted according to the AC power and a driving voltage.

The power terminals P3 and P4 may be connected to a resistor or arectifier circuit, but are not limited thereto.

FIG. 8 is a block diagram of a fluorescent lamp type light emittingapparatus according to an embodiment.

Referring to FIG. 8, the control module 160 may receive power from aballast 181 or an AC power terminal 183. The control module 160 mayreceive a constant current through the ballast 181 connected to a socketfor a fluorescent lamp, or receive current directly from the AC powerterminal 183 without the ballast 181.

The control module 160 comprises a first rectifier unit 161, a secondrectifier unit 162, a voltage-stabilizing unit 163, and an LED controlunit 164.

The first and second rectifier units 161 and 162 may be provided with abridge rectifier circuit, and rectify the input power of the ballast 181or the AC power terminal 183 into DC power. The rectifier circuit of thefirst and second rectifier units 161 and 162 may comprise a rectifierdiode, a condenser, and a resistor, but is not limited thereto.

The voltage-stabilizing unit 163 stabilizes DC power input through thefirst and second rectifier units 161 and 162 into a desired constantpower, and then supplies the desired constant power to the LED controlunit 164.

The LED control unit 164 may convert voltage input from thevoltage-stabilizing unit 163 into phase current, and provide the phasecurrent to the light emitting module 130 to drive the light emittingdiodes.

A sensor unit 170 is disposed at a predetermined position in a cover ofa fluorescent lamp type light emitting apparatus. The sensor unit 170may be disposed under the circuit board 132 of FIG. 1, or at a positionadapted for receiving light. The sensor unit 170, as an optical sensor,senses information about the intensity or amount of light emitted fromthe light emitting diodes 133 of FIG. 1. The sensor unit 170 transmitsthe information of light emitted from the light emitting diodes 133 tothe LED control unit 164, and the LED control unit 164 controlsbrightnesses and colors of the light emitting diodes 133. That is, theLED control unit 164 controls dimming of the light emitting diodes 133by using optical information.

According to another embodiment, an infrared unit or Bluetooth may beprovided, which may function as a switch for remotely controlling on/offof the fluorescent lamp type light emitting apparatus.

According to an embodiment, the fluorescent lamp type light emittingapparatus comprising the LEDs can use the socket for a fluorescent lamp,as a power terminal. According to the embodiment, the light emittingapparatus can be driven by AC power without a ballast, so as to avoidlimitations due to installation of a ballast.

According to an embodiment, color temperatures of the LEDs can be variedto make users feel more comfortable than related art fluorescent lamps.

According to an embodiment, light of the light emitting apparatus issensed to control dimming thereof.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

1. A light emitting apparatus comprising: a cover comprising a firstcover and a second cover coupled to the first cover, wherein the coveris formed in tube shape and at least one of the first cover and secondcover is transmissive; a light emitting module comprising a plurality oflight emitting diodes within the cover; a plurality of radiation pads onthe light emitting module; and cap parts comprising electrode terminalscoupled at both ends of the cover.
 2. The light emitting apparatusaccording to claim 1, wherein the first cover is a heat sink covercomprising a plurality of heat sink pins on at least one of inner andouter surfaces thereof.
 3. The light emitting apparatus according toclaim 2, wherein both edges of the first cover and the second cover areprovided with coupling protrusions and coupling grooves that correspondto each other.
 4. The light emitting apparatus according to claim 3,further comprising an elastic band in the coupling grooves, wherein theelastic band produces a predetermined elastic force to the couplingprotrusions.
 5. The light emitting apparatus according to claim 1,further comprising a diffusion member comprising a diffusion sheet or adiffusion material at an inner circumference of the second cover.
 6. Thelight emitting apparatus according to claim 1, wherein the second covercomprises: an insertion hole therein; and a diffusion sheet in theinsertion hole.
 7. The light emitting apparatus according to claim 1,wherein the plurality of radiation pad comprises silicon material. 8.The light emitting apparatus according to claim 1, wherein each of thecap parts comprises: a guide on an outer circumference thereof; and arotation guide hole formed in the guide, and at least one of the firstcover and the second cover comprises rotation guide protrusions at bothends on an outer circumference thereof, so as to guide rotation of thecover.
 9. The light emitting apparatus according to claim 1, wherein thelight emitting module comprises a circuit board and light emittingdiodes that are arrayed in at least one line under the circuit board,and wherein the radiation pads are disposed on a upper surface of thecircuit board.
 10. The light emitting apparatus according to claim 9,wherein the radiation pads have an upper portion that is in contact withan inner circumference of the first cover.
 11. The light emittingapparatus according to claim 1, further comprising a control modulecontrolling light emitted from the light emitting diode, wherein thelight emitting module comprises a circuit board and a plurality of lightemitting diode arrays under the circuit board.
 12. The light emittingapparatus according to claim 11, wherein the light emitting diode arraysare connected to each other in parallel, and the light emitting diodearrays are each disposed in one of forward and reverse directions. 13.The light emitting apparatus according to claim 11, wherein the lightemitting diode arrays have different color temperature ranges from eachother, and are driven independently from each other.
 14. The lightemitting apparatus according to claim 11, wherein the control modulecomprises: a rectifier unit rectifying power of one of an alternatingcurrent power terminal and a ballast; a voltage-stabilizing unitstabilizing the power rectified by the rectifier unit; and a controlunit controlling driving of a light emitting diode by using outputvoltage of the voltage-stabilizing unit.
 15. The light emittingapparatus according to claim 11, further comprising a sensor unit thatsenses light and transmits information about the sensed light to thelight emitting diode control unit, Wherein the control unit controlsdimming of the light emitting diodes according to the light sensed bythe sensor unit.
 16. The light emitting apparatus according to claim 11,wherein at least one of the first cover and the second cover has ahemispheric shape.
 17. A light emitting apparatus comprising: a lightemitting module comprising a circuit board and a light emitting diodearray under the circuit board; a first cover on the light emittingmodule; a transmissive cover coupled to the first cover; a diffusionmember at the transmissive cover; a plurality of radiation pads on thecircuit board of the light emitting module; and cap parts in both endsof the first cover and the transmissive cover.
 18. The light emittingapparatus according to claim 17, wherein the diffusion member comprisesa diffusion sheet on an inner circumference of the transmissive cover orin the transmissive cover.
 19. The light emitting apparatus according toclaim 17, wherein the circuit board of the light emitting modulecomprises a metal core printed circuit board, and wherein the pluralityof radiation pads comprises silicon material.
 20. The light emittingapparatus according to claim 17, wherein at least one of the first coverand the transmissive cover has a hemispheric shape.